This invention relates to devices for applying heat to the hair to activate permanent wave solutions, hair reconditioners, hair bleachers, or other heat-activated or heat-accelerated solutions used on the hair.
In a process currently used by beauty shops to form permanent waves, a liqiud permanent wave solution is applied to the hair, and the hair is then coiled around a number of rollers placed about the patron's head. Commonly used low-pH permanent wave solutions contain thio-sulphur compounds, or the like, which require heat to activate the permanent wave process. In the most frequently used method of applying heat to the hair, a shower cap is placed over the head, and the patron then sits under a hot air blower which heats the permanent wave solution. During this process of applying heat to the permanent wave, the beautician must frequently remove the shower cap to check the rollers to determine whether processing is complete for each roller. Although this checking is an essential activity, it can be a tedious and time-consuming job because of the failure of the heat source to provide a uniform rate of heat processing over the entire hair structure. The inability to produce a uniform rate of heat processing also requires substantially more processing time.
To reduce the amount of time required to process permanent wave solutions, several alternatives to hot air blowers have been proposed. In one instance, it has been proposed to place an array of infra-red heat lamps around the patron's head. It has also been proposed to use an electrically heated cap which is draped over the patron's head and fits rather loosely around the head. One such heat cap includes a drawstring which ties under the patron's chin. The infra-red lamps and heat caps proposed thus far have not significantly reduced processing time. They also have other disadvantages which make them even less attractive than hot air blowers. For example, a heat lamp array can be very cumbersome to use, and known heat caps have not been developed so they can be easily removed without disturbing the permanent wave when the beautician checks the rollers in the patron's hair.